CN107301306B - Dynamic non-resistance flow prediction method for tight sandstone gas reservoir fractured horizontal well - Google Patents
Dynamic non-resistance flow prediction method for tight sandstone gas reservoir fractured horizontal well Download PDFInfo
- Publication number
- CN107301306B CN107301306B CN201710661222.1A CN201710661222A CN107301306B CN 107301306 B CN107301306 B CN 107301306B CN 201710661222 A CN201710661222 A CN 201710661222A CN 107301306 B CN107301306 B CN 107301306B
- Authority
- CN
- China
- Prior art keywords
- gas
- horizontal well
- fractured horizontal
- dynamic
- flow
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 238000000034 method Methods 0.000 title claims abstract description 54
- 238000004519 manufacturing process Methods 0.000 claims abstract description 60
- 238000012360 testing method Methods 0.000 claims abstract description 58
- 230000035699 permeability Effects 0.000 claims abstract description 38
- 239000007788 liquid Substances 0.000 claims abstract description 19
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 18
- 230000005514 two-phase flow Effects 0.000 claims abstract description 16
- 230000008859 change Effects 0.000 claims abstract description 12
- 239000012530 fluid Substances 0.000 claims abstract description 8
- 230000008878 coupling Effects 0.000 claims abstract description 4
- 238000010168 coupling process Methods 0.000 claims abstract description 4
- 238000005859 coupling reaction Methods 0.000 claims abstract description 4
- 238000004364 calculation method Methods 0.000 claims description 17
- 239000011159 matrix material Substances 0.000 claims description 11
- 230000035945 sensitivity Effects 0.000 claims description 8
- 239000008398 formation water Substances 0.000 claims description 5
- 238000010206 sensitivity analysis Methods 0.000 claims description 5
- 238000009825 accumulation Methods 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 238000004088 simulation Methods 0.000 claims description 3
- 238000011410 subtraction method Methods 0.000 claims description 3
- 238000011161 development Methods 0.000 abstract description 4
- 230000000704 physical effect Effects 0.000 abstract description 2
- 238000011160 research Methods 0.000 abstract description 2
- 239000007789 gas Substances 0.000 description 101
- 239000012071 phase Substances 0.000 description 29
- 101150001310 DPH2 gene Proteins 0.000 description 9
- 239000008346 aqueous phase Substances 0.000 description 3
- 102100024830 2-(3-amino-3-carboxypropyl)histidine synthase subunit 2 Human genes 0.000 description 2
- 208000035126 Facies Diseases 0.000 description 2
- 101000909233 Homo sapiens 2-(3-amino-3-carboxypropyl)histidine synthase subunit 2 Proteins 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000013022 venting Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q50/00—Information and communication technology [ICT] specially adapted for implementation of business processes of specific business sectors, e.g. utilities or tourism
- G06Q50/06—Energy or water supply
Landscapes
- Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Business, Economics & Management (AREA)
- Physics & Mathematics (AREA)
- Economics (AREA)
- Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- General Engineering & Computer Science (AREA)
- Human Resources & Organizations (AREA)
- Evolutionary Computation (AREA)
- Computer Hardware Design (AREA)
- Public Health (AREA)
- Water Supply & Treatment (AREA)
- General Health & Medical Sciences (AREA)
- Geometry (AREA)
- Marketing (AREA)
- Primary Health Care (AREA)
- Strategic Management (AREA)
- Tourism & Hospitality (AREA)
- General Business, Economics & Management (AREA)
- Management, Administration, Business Operations System, And Electronic Commerce (AREA)
Abstract
The invention relates to the field of gas field development research, in particular to a dynamic unobstructed flow prediction method for a fractured horizontal well of a tight sandstone gas reservoir, which comprises the steps of obtaining a gas-liquid two-phase flow capacity equation at any fracture of the fractured horizontal well through coupling of the gas reservoir, the fracture and a shaft; establishing a corresponding numerical model of the fractured horizontal well based on reservoir parameters and fracturing parameters to obtain a relationship curve and a fitting relationship between a dimensionless air leakage boundary and gas testing time; calculating the air leakage boundary of the fractured horizontal well in the production stage by using a dynamic reserve back-stepping method; and solving a gas-liquid two-phase flow productivity equation to obtain the dynamic unobstructed flow of the fractured horizontal well in different production stages based on a phase permeability curve obtained by core testing. The method has the advantages that the difference of the physical property parameters of the reservoir, the change of the fracture parameters, the difference of the non-resistance testing time of the gas well and the influence of external fracturing fluid and stratum movable water on the non-resistance flow are considered, the non-resistance flow of the fractured horizontal well in different production stages can be predicted, and the practicability and the reliability of prediction are improved.
Description
Technical Field
The invention relates to the field of gas field development and research, in particular to a dynamic unobstructed flow prediction method for a tight sandstone gas reservoir fractured horizontal well.
Background
The horizontal well multistage fracturing technology is an important means for realizing economic and effective development of a compact low-permeability gas reservoir, and is widely applied to development of the low-permeability compact gas reservoir at present. There are many published journal literatures at home and abroad about a method for predicting the unimpeded flow of a gas well. Among various non-resistance flow prediction methods reported in the literature at present, no matter a well testing method or an energy production formula method is calculated almost based on gas single-phase seepage, even if the non-resistance flow prediction method considering gas-liquid two-phase flow exists, the influence of non-resistance testing time is not considered, the influence of external fracturing fluid, stratum movable water and fracturing construction on the average permeability of a matrix of a gas well fracturing reconstruction area is not considered, the non-resistance flow is calculated aiming at a gas testing stage, and the practicability and the reliability are lower.
Disclosure of Invention
The invention provides a dynamic non-resistance flow prediction method for a tight sandstone gas reservoir fractured horizontal well, which considers the difference of physical property parameters of a reservoir, the change of fracture parameters, the difference of non-resistance test time of a gas well and the influence of external fracturing fluid and stratum movable water on the non-resistance flow, can predict the non-resistance flow of the fractured horizontal well in different production stages, and improves the practicability and reliability of prediction.
In order to achieve the technical purpose, the technical scheme adopted by the invention is as follows:
the dynamic unobstructed flow prediction method for the tight sandstone gas reservoir fractured horizontal well is characterized by comprising the following steps of:
the method comprises the following steps: the gas-liquid two-phase flow capacity equation at any crack of the fractured horizontal well is as follows: based on a gas-liquid two-phase seepage theory, according to the influence of reservoir stress sensitivity, crack parameters and high-speed non-Darcy flow in the crack, a potential function superposition principle and gas-water two-phase generalized simulated pressure are utilized, and a gas-liquid two-phase flow capacity equation at any crack of the fractured horizontal well is obtained through coupling of a gas reservoir, the crack and a shaft;
step two: and (3) determining a deflation boundary in a test gas phase: establishing a corresponding fractured horizontal well numerical model based on reservoir parameters and fracturing parameters, simulating the change of a gas leakage boundary along with time according to average gas production by combining with the yield control requirement of a gas well in a fracturing flow-back stage, defining a dimensionless gas leakage boundary as the ratio of the distance from a coordinate origin to the gas leakage boundary in the X-axis direction to the length of 1/2 fractured horizontal well, and fitting according to a simulation result to obtain a relation curve and a fitting relation between the dimensionless gas leakage boundary and test gas time;
step three: determination of the deflation boundary in the production phase: based on the dynamic production data of the fractured horizontal well, calculating the dynamic reserve of the fractured horizontal well by adopting an oil pressure subtraction method, a yield accumulation method and a material balance method, and calculating the gas leakage boundary of the fractured horizontal well at the production stage by utilizing a dynamic reserve back-pushing method, wherein the dynamic reserve back-pushing method is to obtain the gas leakage boundary of the fractured horizontal well at the production stage by combining the volume method of dynamic reserve calculation;
step four: dynamic unobstructed flow of fractured horizontal wells at different production stages: and on the basis of a phase permeability curve obtained by core testing, according to the gas leakage boundaries of different production stages and corresponding well bottom flowing pressure and gas production rate test values, setting iteration solving precision and a proper effective permeability range, performing Newton iteration solving on the gas-liquid two-phase flow capacity equation in the step one, and obtaining the effective permeability of the matrix and the inflow dynamic IPR curve of the fractured horizontal well under the influence of external fracturing fluid and formation water around the well by an interpolation fitting method, thereby obtaining the dynamic unimpeded flow of the fractured horizontal well in different production stages.
Further, the second step of establishing the numerical model of the fractured horizontal well requires setting the size of the model according to the actual well pattern and well spacing of the gas reservoir, setting fracture parameters, and setting different time step lengths according to the influence of stress sensitivity to obtain the change of the air leakage boundary at the initial production stage.
Further, when calculating the air leakage boundary of the fractured horizontal well by using a dynamic reserve back-stepping method in the third step, the shape of the air leakage boundary of the fractured horizontal well needs to be approximately equivalent to a combination of a rectangle and two semicircles, and the influence of the residual gas saturation in the facies permeability curve, the air leakage boundary r is calculated by using the dynamic reserve back-stepping method, and a specific calculation equation is as follows:
wherein:
r-air leakage boundary, unit is m; phi-porosity, decimal; l-horizontal well length, m; h is the gas layer thickness, m; gp-dynamic reserves, ten thousand; b isgi-original volume factor, decimal, of the gas; swc-irreducible water saturation, decimal; sgorIrreducible water saturation, decimal.
Further, when the unobstructed flow in the air test stage is iteratively solved according to the calculated air leakage boundary in the fourth step, the sensitivity analysis of the air leakage boundary on the inflow dynamic IPR curve is required according to the effective permeability of the matrix obtained by fitting; and determining the minimum value of the dimensionless air leakage boundary during the non-resistance flow calculation in the air test stage according to the intersection method, if the dimensionless air leakage boundary during the non-resistance flow calculation is smaller than the dimensionless air leakage boundary minimum value, selecting the dimensionless air leakage boundary minimum value to calculate the non-resistance flow, and avoiding the condition that the non-resistance flow is larger due to too short test time.
The beneficial effects produced by the invention are as follows:
the method simultaneously considers the difference of reservoir stratum parameters, the change of fracture parameters, the difference of gas well unobstructed test time and the influence of external fracturing fluid and stratum movable water on unobstructed flow, can predict the unobstructed flow of the fractured horizontal well in different production stages, and overcomes the defects of the conventional unobstructed flow test. The method has the advantages of comprehensive consideration, high reliability of the calculation result, strong practicability and good popularization and use values.
Drawings
FIG. 1 is a flow chart of the dynamic unobstructed flow calculation steps of the present invention;
FIG. 2 is a numerical model pressure profile of a fractured horizontal well of an embodiment;
FIG. 3 is a graph of the relationship between dimensionless leak-off boundary and time at a test gas stage of a fractured horizontal well according to an embodiment;
FIG. 4 is a graph of the relationship between the unobstructed flow and the dimensionless leak-off boundary at the gas testing phase of the fractured horizontal well of the embodiment;
FIG. 5 is a graph of measured production data versus IPR during the pilot gas phase of the example;
FIG. 6 is a graph of measured production data versus IPR for the production phase of the example;
FIG. 7 is a graph of pressure change of a DPH-2 well production curve of an example;
FIG. 8 is a graph of the production variation of the DPH-2 well production profile of the example.
Detailed Description
The invention will be described in more detail below with reference to the drawings and specific examples, but the scope of the invention is not limited thereto.
As shown in fig. 1, a dynamic unobstructed flow prediction method for a tight sandstone gas reservoir fractured horizontal well comprises the following steps:
1) based on a gas-liquid two-phase seepage theory, considering the influence of reservoir stress sensitivity and high-speed non-Darcy flow in the fracture, and by utilizing a potential function superposition principle and gas-water two-phase generalized pseudo-pressure, obtaining a gas-liquid two-phase flow capacity equation at any fracture of the fractured horizontal well through coupling of a gas reservoir, the fracture and a shaft:
wherein:
ψethe gas-water two-phase pseudo pressure corresponding to the boundary pressure, with the unit of × 106g/(mD·m·d)；ψwfj-gas-water two-phase pseudo pressure corresponding to bottom hole flowing pressure, unit is×106g/(mD.m.d); h is the gas layer thickness in m; k is a radical ofi-effective permeability of the matrix in mD; k is a radical ofrg-gas phase relative permeability, decimal; k is a radical ofrwRelative permeability of aqueous phase, decimal, α stress sensitivity coefficient, unit is MPa-1；qgscfiGas flow rate of i-th crack under standard conditions, in m3/d；ρgscGas phase density in g/cm under standard conditions3；ρwscDensity of the aqueous phase in g/cm under standard conditions3；ρgGas phase density in g/cm3；ρwDensity of the aqueous phase in g/cm3(ii) a m-when the number of cracks N is odd, -N0+ j-1, the number of cracks N is even-number, -N0+2(j-1)；Xf-half crack length in m; d, when the number N of the cracks is an odd number, the crack spacing is the crack half spacing, and when the number N of the cracks is an even number, the unit is m; n is a radical of0-the number of cracks N is (N-1)/2 when it is an odd number, and N-1 when it is an even number; w-crack width in m, μg-gas viscosity in mPa · s; mu.sw-formation water viscosity in mPa · s; r is the equivalent deflation radius of the high-speed Darcy flow in the crack, and the unit is m; rwg-production water to gas ratio, decimal; r isw-wellbore radius in m; r is the equivalent air leakage radius of any point of the high-speed Darcy flow in the crack, and the unit is m; r ise-a venting boundary in m; k is a radical off-fracture permeability in mD; p is a radical ofi-virgin formation pressure in MPa; p-formation pressure in MPa.
2) And (3) determining a deflation boundary in a test gas phase: establishing a corresponding fractured horizontal well numerical model by utilizing Comsol simulation software based on actual reservoir parameters and fracturing parameters; combining the gas well yield control requirement of the fracturing flow-back stage, simulating the change of the gas leakage boundary along with the time according to the average gas production, and obtaining a relation curve of the dimensionless gas leakage boundary and the gas testing time and a fitting relation d of 0.905t0.0319。
The numerical model of the fractured horizontal well is established by setting the size of the model according to the actual well pattern well spacing of the gas reservoir, setting fracture parameters, considering the influence of stress sensitivity, and setting different time step lengths according to the day to obtain the change of the air leakage boundary at the initial production stage.
3) Based on a phase permeability curve obtained by core testing, according to a gas-liquid two-phase flow productivity formula in a gas testing stage, a relation curve and a fitting relation of a dimensionless gas leakage boundary and gas testing time and corresponding bottom hole flow pressure and gas production testing values, iterative solution accuracy and a proper effective permeability range are set, Newtonian iterative solution is carried out on a gas-liquid two-phase flow productivity equation, and the effective permeability of a matrix under the influence of external fracturing fluid and formation water around a well is obtained through an interpolation fitting method.
4) And (3) carrying out sensitivity analysis on the gas leakage boundary in the gas testing stage, determining the minimum value of the dimensionless gas leakage boundary in the gas testing stage, setting iterative solution precision by combining the bottom hole flowing pressure, the gas production rate test value and the gas testing time, and calculating an inflow dynamic IPR curve of the fractured horizontal well by using a gas-liquid two-phase flow capacity equation so as to determine the non-resistance flow in the gas testing stage.
5) Determination of the deflation boundary in the production phase: based on the dynamic production data of the fractured horizontal well, the dynamic reserves of the fractured horizontal well are respectively calculated by adopting an oil pressure subtraction method, a yield accumulation method and a material balance method, and the air leakage boundary of the fractured horizontal well is obtained by combining the volume method of dynamic reserve calculation and reverse deduction.
When the dynamic reserve back-stepping method is adopted to calculate the air leakage boundary of the fractured horizontal well, the shape of the air leakage boundary of the fractured horizontal well can be approximately equivalent to the combination of a rectangle and two semicircles according to the numerical simulation result; then, when calculating the air leakage boundary according to a dynamic reserve inverse method, the influence of residual air saturation in a phase permeability curve needs to be considered, otherwise, the calculation result is slightly small, and a specific calculation equation is as follows:
wherein:
r-air leakage boundary, unit is m; phi-porosity, decimal; l is the length of the horizontal well, and the unit is m; h-thickness of gas layerIn the unit of m; gp-dynamic reserves in units of ten thousand squares; b isgi-original volume factor, decimal, of the gas; swc-irreducible water saturation, decimal; sgorIrreducible water saturation, decimal.
6) Based on a phase permeability curve obtained by core testing, according to the air leakage boundary values calculated in different production stages and corresponding bottom hole flowing pressure and gas production rate test values, iterative solution precision and a proper effective permeability range are set, Newton iterative solution is carried out on a gas-liquid two-phase flow capacity equation, and the effective permeability of a matrix and an inflow dynamic IPR curve of a fractured horizontal well under the influence of external fracturing fluid and formation water around the well are obtained through an interpolation fitting method, so that the dynamic unimpeded flow of the fractured horizontal well in different production stages is obtained.
According to the calculated air leakage boundary, when the non-resistance flow in the air test stage is solved in an iterative manner, the sensitivity analysis of the air leakage boundary is needed to be carried out on an inflow dynamic IPR curve according to the effective permeability of the matrix obtained by fitting, the minimum value of the non-dimensional air leakage boundary in the air test stage during the calculation of the non-resistance flow is determined according to an intersection method, if the non-dimensional air leakage boundary during the non-resistance prediction is smaller than the minimum value of the non-dimensional air leakage boundary, the minimum value of the non-dimensional air leakage boundary is selected to calculate the non-resistance flow, and the situation that the non-resistance flow is larger due to the fact that the test time is too short.
The invention is explained in more detail below with reference to specific embodiments:
the DPH-2 well of the Daniu field D12 well area uses a box 1 layer as a target layer, the thickness of the gas layer is 11m, the length of a horizontal section of a real drill is 1000m, the average porosity of the horizontal section is 10.3%, the average permeability is 0.69mD, the average gas saturation is 52.1%, and the stress sensitivity coefficient is 0.47. The actual number of fracturing cracks is 11, the half length of the cracks is 150m, the flow conductivity of the cracks is 40D cm, a flow pressure test is carried out 14 days after fracturing flowback, and the flow pressure in the middle of the stratum is 13.573MPa, the static pressure of the stratum is 23.7MPa and the average daily gas production rate is 84427m3And d, the PVT parameters of the natural gas of the gas layer are shown in a table 1, the phase permeation data are shown in a table 2, and the data are basic data for establishing a numerical model and solving a gas-liquid two-phase flow capacity equation.
Table 1 box 1 reservoir gas PVT parameters
| Pressure, Mpa | Volume factor, rm3/sm3 | Viscosity, mPas |
| 7.342 | 0.0158 | 0.0145 |
| 8.349 | 0.0138 | 0.0147 |
| 9.33 | 0.0123 | 0.0149 |
| 10.321 | 0.0111 | 0.0151 |
| 11.314 | 0.0101 | 0.0154 |
| 12.291 | 0.0092 | 0.0156 |
| 13.286 | 0.0085 | 0.0159 |
| 14.285 | 0.0079 | 0.0162 |
| 15.294 | 0.0074 | 0.0166 |
| 16.273 | 0.0070 | 0.0169 |
| 17.279 | 0.0066 | 0.0172 |
| 18.25 | 0.0063 | 0.0176 |
| 19.211 | 0.0060 | 0.0179 |
| 20.203 | 0.0057 | 0.0183 |
| 21.211 | 0.0054 | 0.0187 |
| 22.208 | 0.0052 | 0.0191 |
| 23.16 | 0.0050 | 0.0195 |
| 24.209 | 0.0049 | 0.0199 |
| 25.198 | 0.0047 | 0.0203 |
| 26.155 | 0.0046 | 0.0207 |
| 27.086 | 0.0044 | 0.0210 |
| 28.174 | 0.0043 | 0.0214 |
| 29.178 | 0.0042 | 0.0218 |
TABLE 2 Box 1 reservoir facies permeability curve data sheet
| Gas saturation (%) | Relative permeability of gas phase | Relative permeability of water phase |
| 16.00 | 0 | 0.5950 |
| 18.90 | 0.0021 | 0.5207 |
| 21.80 | 0.0074 | 0.4518 |
| 24.69 | 0.0153 | 0.3882 |
| 27.59 | 0.0257 | 0.3298 |
| 30.49 | 0.0383 | 0.2765 |
| 33.39 | 0.0532 | 0.2283 |
| 36.29 | 0.0703 | 0.1852 |
| 39.19 | 0.0893 | 0.1468 |
| 42.08 | 0.1104 | 0.1133 |
TABLE 2 continuation
| Gas saturation (%) | Relative permeability of gas phase | Relative permeability of water phase |
| 44.98 | 0.1335 | 0.0845 |
| 47.88 | 0.1585 | 0.0602 |
| 50.78 | 0.1854 | 0.0403 |
| 53.68 | 0.2141 | 0.0247 |
| 56.58 | 0.2447 | 0.0131 |
| 59.47 | 0.2770 | 0.0054 |
| 62.37 | 0.3111 | 0.0012 |
| 65.27 | 0.3470 | 0 |
1) And (3) determining a deflation boundary in a test gas phase: and establishing a corresponding numerical model of the fractured horizontal well by using Comsol simulation software in combination with actual reservoir parameters and fracturing parameters of the DPH-2 well. Combining the yield control requirement of the gas well in the fracturing flow-back stage, simulating the change of the gas leakage boundary along with the time according to the average gas production, triangularly subdividing the grid, defining the time step length as 1 day, simulating the change condition of the gas leakage boundary in 60 days, wherein the distribution condition of the gas leakage boundary of the gas well in 20 days is shown in figure 2, defining the dimensionless gas leakage boundary as the distance from the coordinate origin to the gas leakage boundary in the X-axis direction and the ratio of 1/2 fracturing horizontal well length, and obtaining the relationship curve and the fitting relationship of the dimensionless gas leakage boundary and the gas testing time:
d＝0.905t0.0319
wherein: d-dimensionless air leakage boundary, decimal; t-time, day.
The relationship curve of the dimensionless air leakage boundary and the air test time is shown in fig. 3: the dimensionless air leakage boundary at the initial stage of air test increases rapidly along with the increase of the air test time, and the increase speed of the dimensionless air leakage boundary is obviously reduced when the air test time exceeds 20 days.
2) Based on a phase permeability curve obtained by core testing, based on actual reservoir parameters and fracturing parameters of a DPH-2 well, a gas-liquid two-phase flow capacity formula and a fitting relation of a dimensionless gas release boundary and a gas test time are utilized, the effective permeability range of the reservoir is set to be 0.01 mD-2 mD by combining fracturing flowback time, the flowing pressure of gas test, static pressure and gas production data, the effective permeability range of the reservoir is obtained to be 0.01 mD-2 mD, the effective permeability of a fitting matrix is obtained by Newton iteration solution, when the barrier-free flow in the gas test stage is solved in an iteration mode according to the calculated gas release boundary, sensitivity analysis of the gas release boundary is needed to be carried out on an IPR curve according to the effective permeability of the matrix obtained by fitting, the minimum value of the dimensionless gas release boundary in calculation of the barrier-free flow in the gas test stage is determined to be 1 according to an intersection method, as shown in figure 4, the gas well gas release flow is gradually reduced along with, if the dimensionless air leakage boundary during the dimensionless prediction is smaller than the dimensionless air leakage boundary minimum value, the dimensionless air leakage boundary minimum value is selected to calculate the dimensionless flow, so that the situation that the dimensionless flow is larger due to too short test time is avoided.
3) And (3) performing a flow pressure test 14 days after fracturing flow-back, correcting the dimensionless air leakage boundary to be 1 when testing air, and calculating to obtain a DPH-2 well inflow dynamic curve after correcting the air leakage boundary in the air testing stage, wherein as shown in fig. 5, the corresponding non-resistance flow is 9.80 ten thousand square/day, and the production is allocated according to 1/5-1/3 of the non-resistance flow, and the initial reasonable allocation range is 1.96 ten thousand square/day-3.27 ten thousand square/day. As shown in fig. 7 and 8, the pressure drop rate of the DPH2 well production curve is relatively high at an initial production rate of 4 ten thousand square meters per day (normal one-point unimpeded flow rate is 12.37 ten thousand square meters per day), the production rate is adjusted to be about 3.2 ten thousand square meters per day after 40 days of production, the pressure drop rate is remarkably slowed, the gas well achieves stable production for about 2 years, and the unimpeded flow rate obtained by the calculation method in the gas testing stage is high in reliability.
4) 11/12/2014, based on the dynamic production data of the fractured horizontal well: the flow pressure test data of the DPH-2 well is 6.84MPa of flow pressure and 31038 square days of daily gas production, the dynamic reserves of the DPH-2 well are respectively calculated according to an accumulated yield method, an oil pressure decreasing method and a flowing substance balancing method, as shown in table 3, the average dynamic reserve of the three methods is 4551.06 ten thousand square, and the air leakage boundary of the fractured horizontal well is obtained by combining a volume method for calculating the dynamic reserves and performing reverse deduction, so the air leakage boundary of the fractured horizontal well is 674.65m by combining the calculation of the phase permeability data. Setting the effective permeability range of the reservoir to be 0.01-2 mD, calculating the inflow dynamic curve of the gas well through Matlab programming, and obtaining the fitting effective permeability of 0.24mD at the moment, wherein the unimpeded flow of the gas well is 3.32 ten thousand square/day, and as shown in FIG. 6, the reasonable production allocation is 0.6637-1.1061 ten thousand square/day at the moment. The pressure and yield changes of the production curve of the DPH2 well are shown in figures 7 and 8, in 12 months in 2014, due to the fact that the well head pressure is low and the pressure drop rate is high, the well is produced by using a speed pipe instead, the production rate is adjusted to be about 1.0 ten thousand square/day, the gas well enters the second stable production stage to produce, the reasonable production rate obtained by the method is consistent with the reasonable production rate obtained by the method, and the non-resistance flow rate result of the gas well in the production stage calculated by the method is high in reliability.
TABLE 3 dynamic reserves calculation results corresponding to different production stages of the DPH-2 well
It should be noted that the above-mentioned embodiments illustrate rather than limit the technical solutions of the present invention, and that equivalent substitutions or other modifications made by persons skilled in the art according to the prior art are included in the scope of the claims of the present invention as long as they do not exceed the spirit and scope of the technical solutions of the present invention.
Claims (4)
1. The dynamic unobstructed flow prediction method for the tight sandstone gas reservoir fractured horizontal well is characterized by comprising the following steps of:
the method comprises the following steps: the gas-liquid two-phase flow capacity equation at any crack of the fractured horizontal well is as follows: based on a gas-liquid two-phase seepage theory, according to the influence of reservoir stress sensitivity, crack parameters and high-speed non-Darcy flow in the crack, a potential function superposition principle and gas-water two-phase generalized simulated pressure are utilized, and a gas-liquid two-phase flow capacity equation at any crack of the fractured horizontal well is obtained through coupling of a gas reservoir, the crack and a shaft;
step two: and (3) determining a deflation boundary in a test gas phase: establishing a corresponding fractured horizontal well numerical model based on reservoir parameters and fracturing parameters, simulating the change of a gas leakage boundary along with time according to average gas production by combining with the yield control requirement of a gas well in a fracturing flow-back stage, defining a dimensionless gas leakage boundary as the ratio of the distance from a coordinate origin to the gas leakage boundary in the X-axis direction to the length of 1/2 fractured horizontal well, and fitting according to a simulation result to obtain a relation curve and a fitting relation between the dimensionless gas leakage boundary and test gas time;
step three: determination of the deflation boundary in the production phase: based on the dynamic production data of the fractured horizontal well, calculating the dynamic reserve of the fractured horizontal well by adopting an oil pressure subtraction method, a yield accumulation method and a material balance method, and obtaining an air leakage boundary of the fractured horizontal well in the production stage according to a dynamic reserve reverse pushing method;
step four: dynamic unobstructed flow of fractured horizontal wells at different production stages: and on the basis of a phase permeability curve obtained by core testing, according to the gas leakage boundaries of different production stages and corresponding well bottom flowing pressure and gas production rate test values, setting iteration solving precision and an effective permeability range, carrying out Newton iteration solving on the gas-liquid two-phase flow capacity equation in the step I, and obtaining the effective permeability of the matrix and the inflow dynamic IPR curve of the fractured horizontal well under the influence of external fracturing fluid and formation water around the well by an interpolation fitting method, thereby obtaining the dynamic unimpeded flow of the fractured horizontal well in different production stages.
2. The dynamic unobstructed flow prediction method for tight sandstone gas reservoir fractured horizontal well according to claim 1, wherein the fractured horizontal well numerical model in the second step is established by setting fracture parameters according to the size of the model set by the actual well pattern well spacing of the gas reservoir, and setting different time step lengths according to the influence of stress sensitivity to obtain the change of the air leakage boundary at the initial production stage.
3. The dynamic unobstructed flow prediction method for the tight sandstone gas reservoir fractured horizontal well according to claim 1, wherein when the dynamic reserve back-stepping method is adopted to calculate the fractured horizontal well gas leakage boundary in the third step, the shape of the fractured horizontal well gas leakage boundary needs to be approximately equivalent to a combination of a rectangle and two semicircles, and the influence of residual gas saturation in a phase permeability curve is adopted to calculate the gas leakage boundary r by adopting the dynamic reserve back-stepping method, and the specific calculation equation is as follows:
wherein:
r-air leakage boundary, unit is m; phi-porosity, decimal; l-horizontal well length, m; h is the gas layer thickness, m; gp-dynamic reserves, ten thousand; b isgi-original volume factor, decimal, of the gas; swc-irreducible water saturation, decimal; sgorIrreducible water saturation, decimal.
4. The dynamic unobstructed flow prediction method for tight sandstone gas reservoir fractured horizontal well according to claim 1, wherein in the fourth step, when the unobstructed flow in the gas testing phase is solved iteratively according to the calculated air leakage boundary, sensitivity analysis of the air leakage boundary needs to be performed on the inflow dynamic IPR curve according to the effective permeability of the matrix obtained by fitting; and determining the minimum value of the dimensionless air leakage boundary during the non-dimension flow calculation in the air test stage according to the intersection method, and if the dimensionless air leakage boundary during the non-dimension flow calculation is smaller than the dimensionless air leakage boundary minimum value, selecting the dimensionless air leakage boundary minimum value to calculate the non-dimension flow.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710661222.1A CN107301306B (en) | 2017-08-04 | 2017-08-04 | Dynamic non-resistance flow prediction method for tight sandstone gas reservoir fractured horizontal well |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710661222.1A CN107301306B (en) | 2017-08-04 | 2017-08-04 | Dynamic non-resistance flow prediction method for tight sandstone gas reservoir fractured horizontal well |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107301306A CN107301306A (en) | 2017-10-27 |
| CN107301306B true CN107301306B (en) | 2020-09-15 |
Family
ID=60134490
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710661222.1A Expired - Fee Related CN107301306B (en) | 2017-08-04 | 2017-08-04 | Dynamic non-resistance flow prediction method for tight sandstone gas reservoir fractured horizontal well |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107301306B (en) |
Families Citing this family (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11414975B2 (en) | 2014-07-14 | 2022-08-16 | Saudi Arabian Oil Company | Quantifying well productivity and near wellbore flow conditions in gas reservoirs |
| CN108150158B (en) * | 2017-12-13 | 2021-05-11 | 西安石油大学 | Deep fractured compact sandstone gas reservoir early water body analysis and prediction method |
| CN108197377B (en) * | 2017-12-27 | 2021-08-03 | 中国石油化工股份有限公司 | Gas-liquid two-phase throttling critical flow calculation method and device |
| CN108331555B (en) * | 2018-02-01 | 2020-07-10 | 中国地质大学（北京） | Method for exploiting sulfur-containing gas reservoir of carbonate rock |
| CN108798648A (en) * | 2018-06-07 | 2018-11-13 | 西南石油大学 | A kind of hypotonic tight gas reservoir improvement positive sequence modified isochronal test method |
| CN110939430B (en) * | 2018-09-20 | 2022-09-06 | 中国石油化工股份有限公司 | Method for determining shale gas fracturing fluid flowback model |
| CN111005715B (en) * | 2018-10-08 | 2023-02-28 | 中国石油天然气股份有限公司 | Method and device for determining yield of gas well and storage medium |
| CN109522634B (en) * | 2018-11-09 | 2022-08-19 | 中国石油天然气集团有限公司 | Numerical analysis method for compact gas multistage volume fracturing horizontal well |
| CN111353205B (en) * | 2018-12-20 | 2022-10-04 | 中国石油化工股份有限公司 | Method for calculating formation pressure and dynamic productivity of water-producing gas well of tight gas reservoir |
| CN111400853B (en) * | 2019-01-03 | 2022-10-04 | 中国石油天然气股份有限公司 | Method and device for predicting unsteady state capacity of closed boundary fractured horizontal well |
| CN111691863B (en) * | 2019-03-14 | 2022-08-02 | 中国石油天然气股份有限公司 | Reservoir fracturing method and device |
| CN112049624B (en) * | 2019-06-06 | 2024-04-30 | 中国石油天然气股份有限公司 | Method, device, equipment and storage medium for predicting dynamic reserve of oil well |
| CN112324428B (en) * | 2019-08-05 | 2023-08-22 | 中国石油天然气股份有限公司 | Method, device and computer storage medium for correcting inflow dynamic curve of gas well |
| CN113047827A (en) * | 2019-12-27 | 2021-06-29 | 中国石油化工股份有限公司 | Horizontal well yield prediction method and device |
| WO2021247378A1 (en) * | 2020-06-02 | 2021-12-09 | Saudi Arabian Oil Company | Quantifying well productivity and near wellbore flow conditions in gas reservoirs |
| CN111694856B (en) * | 2020-06-11 | 2021-03-12 | 中国石油大学(北京) | Intelligent prediction method and device for reservoir sensitivity |
| US11326450B2 (en) | 2020-06-11 | 2022-05-10 | China University Of Petroleum (Beijing) | Intelligent prediction method and apparatus for reservoir sensitivity |
| CN113931621B (en) * | 2020-07-14 | 2023-08-22 | 中国石油天然气股份有限公司 | Method, device and storage medium for determining gas well hydrops information |
| CN111810119B (en) * | 2020-07-21 | 2022-06-28 | 重庆科技学院 | Method for calculating productivity of gas well of high-pressure carbonate rock having water gas reservoir |
| CN111810141B (en) * | 2020-07-30 | 2023-07-25 | 中国石油天然气股份有限公司 | Method for predicting final accumulated gas production of gas-production well |
| CN112182992B (en) * | 2020-09-29 | 2023-07-25 | 西北大学 | Method for optimizing fracture position of horizontal well section fracturing of tight sandstone gas reservoir |
| CN115247548A (en) * | 2021-04-26 | 2022-10-28 | 中国石油化工股份有限公司 | Differential production allocation method for water-containing compact gas reservoir gas well |
| CN115680592B (en) * | 2021-07-28 | 2024-06-25 | 中国石油天然气股份有限公司 | Method, device, equipment and storage medium for determining fracturing effectiveness parameters |
| CN114893154B (en) * | 2022-05-24 | 2023-03-31 | 西安石油大学 | Dynamic optimization method for bottom-edge water gas reservoir horizontal well production allocation |
| CN115126473B (en) * | 2022-06-29 | 2023-08-15 | 重庆科技学院 | Calculation method for standardized test yield of shale gas well |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102128031A (en) * | 2011-01-11 | 2011-07-20 | 西南石油大学 | Simulation device and method for researching horizontal well gas-liquid two-phase pipe flow mechanism |
| CN103256035A (en) * | 2013-05-22 | 2013-08-21 | 中国石化集团华北石油局 | Fracturing fracture geological design method of horizontal well of dense gas field |
| WO2013149122A1 (en) * | 2012-03-29 | 2013-10-03 | Schlumberger Canada Limited | Additive for subterranean treatment |
| CN104933243A (en) * | 2015-06-12 | 2015-09-23 | 浙江大学 | Method for simulating gas-liquid two-phase flow |
| CN105507893A (en) * | 2015-12-07 | 2016-04-20 | 西南石油大学 | Method for predicting production effect of shale reservoir after size modification |
| CN106547930A (en) * | 2015-09-16 | 2017-03-29 | 中国石油化工股份有限公司 | Consider the gas drainage radius computational methods of tight gas reservoir seepage flow mechanism |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150331976A1 (en) * | 2014-05-15 | 2015-11-19 | Schlumberger Technology Corporation | Forecasting oil production for multiply-fractured horizontal wells |
-
2017
- 2017-08-04 CN CN201710661222.1A patent/CN107301306B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102128031A (en) * | 2011-01-11 | 2011-07-20 | 西南石油大学 | Simulation device and method for researching horizontal well gas-liquid two-phase pipe flow mechanism |
| WO2013149122A1 (en) * | 2012-03-29 | 2013-10-03 | Schlumberger Canada Limited | Additive for subterranean treatment |
| CN103256035A (en) * | 2013-05-22 | 2013-08-21 | 中国石化集团华北石油局 | Fracturing fracture geological design method of horizontal well of dense gas field |
| CN104933243A (en) * | 2015-06-12 | 2015-09-23 | 浙江大学 | Method for simulating gas-liquid two-phase flow |
| CN106547930A (en) * | 2015-09-16 | 2017-03-29 | 中国石油化工股份有限公司 | Consider the gas drainage radius computational methods of tight gas reservoir seepage flow mechanism |
| CN105507893A (en) * | 2015-12-07 | 2016-04-20 | 西南石油大学 | Method for predicting production effect of shale reservoir after size modification |
Non-Patent Citations (3)
| Title |
|---|
| Dual Porosity and Dual Permeability Modeling of Horizontal Well in Naturally Fractured Reservoir;Ren-Shi Nie 等;《Transp Porous Med》;-;20111102;第213-235页 * |
| 致密气田水平井压裂缝地质设计优化研究-以大牛地气田为例;任广磊 等;《石油地质与工程》;20150131;第29卷(第1期);第89-91页 * |
| 致密气藏水平井速度管下入时间确定方法;吴武超 等;《断块油气田》;20150731;第22卷(第4期);第522-525页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107301306A (en) | 2017-10-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107301306B (en) | Dynamic non-resistance flow prediction method for tight sandstone gas reservoir fractured horizontal well | |
| CN107045671B (en) | Method for predicting liquid accumulation risk of water producing gas well | |
| CN107622328B (en) | A kind of more cluster pressure break horizontal well production prediction methods of shale gas reservoir segmentation | |
| CN104018829B (en) | A kind of method that utilization coal bed gas well creation data measures air water phase percolation curve | |
| CN111236908A (en) | Multi-stage fractured horizontal well productivity prediction model and productivity sensitivity analysis method suitable for low-permeability tight gas reservoir | |
| CN103590824B (en) | Capacity calculation method for compact gas reservoir horizontal well after multi-section fracturing modification | |
| CN103902827B (en) | Flow unit division method of carbonate-rock horizontal wells | |
| CN107526891B (en) | Polymer flooding large-pore oil reservoir well testing analysis method | |
| CN110147561B (en) | Method for predicting volume fracture network of tight oil and gas reservoir containing natural fracture | |
| CN107462936B (en) | Utilize the method for pressure monitoring Data Inversion low permeability reservoir non-Darcy percolation law | |
| CN106599449A (en) | Well test explanation method for cave volume calculation | |
| CN105178939B (en) | A kind of prediction technique for channel pressure break flow conductivity | |
| CN101806224B (en) | Method for predicting extraction productivity of underground coal-seam gas | |
| CN111353205B (en) | Method for calculating formation pressure and dynamic productivity of water-producing gas well of tight gas reservoir | |
| CN105547967B (en) | Fissuted medium system permeability tensor indoor measurement device | |
| CN104568694A (en) | Method for testing gas-water relative permeability of dense core | |
| CN103761448B (en) | Adjustable weight parameter determination method in coal seam floor water inrush variable weight vulnerability evaluation method | |
| CN108920849A (en) | A kind of fractured-vuggy reservoir well testing determines hole method of flow in stratum | |
| CN109424362B (en) | Method and system for calculating single-well control crude oil reserve of bottom water reservoir | |
| CN114427432B (en) | Method for determining development potential of residual gas in gas reservoir | |
| CN105443093B (en) | Well head combined measuring device and its method for injection well | |
| CN108133087A (en) | A kind of Gas-water phases seepage stress sensitivity reservoir original permeability inversion method | |
| CN112257349B (en) | Method for judging whether tight sandstone movable water-gas reservoir gas well has development value | |
| CN114880962A (en) | Stratum seepage-shaft pipe flow coupling-based integrated analysis method for single-well injection and production capacity of tight gas reservoir | |
| CN106545335A (en) | Method for determining failure type development reasonable production pressure difference of tight oil reservoir |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20200915 Termination date: 20210804 |